The present invention relates generally to a submersible pump assembly with an electrical drive motor.
Basically, two types of submersible pump assemblies are known from the state of the art. There are submersible pump assemblies with an electrical drive motor, which includes an electronic control or regulation device for the operation of the electrical drive motor. The device being arranged directly on the submersible electrical drive motor. These submersible pump assemblies merely require an electrical mains connection lead which leads into the pump sump. However, they provide no external control or monitoring possibilities at all.
Moreover, submersible pump assemblies are known, which include an external control and regulation device which is arranged outside the pump sump and which is connected via an electrical connection lead to the submerged drive motor in the pump sump. In the case that sensors such as for example level sensors in the pump sump are yet necessary for the operation of this submersible pump assembly, these sensors must likewise be connected via electrical leads to the control or regulation device outside the pump sump, so that numerous lead connections are necessary.
A submersible pump assembly is shown in FIG. 1, which once again explains the state of the art. In the state of the art, it is known to arrange a submersible pump 4, consisting of a drive motor and the actual pump, in a pump sump 2. The submersible pump 4 is connected via a lead 8 to an external control device 6 which is arranged outside the pump sump 2. The lead 8 serves for the energy supply of the submersible pump 4 or of its drive motor. The switching of the submersible pump 4 on and off is thereby effected via the control device 6. The control device 6 may furthermore for example also yet contain a frequency converter for activating the drive motor of the submersible pump 4. Moreover, the control device 6 is connected via leads 12 to sensors 10 in the pump sump 2. The sensors 10 may for example be pressure sensors, level switches, temperature sensors etc. The control device 6 controls the submersible pump 4 in dependence on the output signals of the sensors 10, in particular the control device 6 switches the submersible pump 4 on and off in dependence on the signals. It is to be understood that here several leads 8 and 12 need to be led out of the pump sump to the control device 6.